Mulch barriers, such as landscaping films, are commonly placed underneath the mulch used in landscaping around shrubs, trees, and decorative plants. The mulch barrier reduces weed growth and extends the life of the mulch by keeping it away from the soil. A non-porous plastic sheet, such as black plastic, provides excellent mulch life and weed control. However, a plastic sheet excludes water and air from the earth beneath it, often resulting in the death of, or damage to, the plants around which it is placed.
By perforating the plastic sheet, air and water can pass through the plastic sheet to the soil. However, mulch lying on top of the holes tends to block them, resulting in the problems mentioned above. Placing a greater number of holes in the sheet tends to alleviate the problem of blocked holes, but reduces the ability of the barrier to provide weed control.
Using a fabric material as a mulch barrier allows water and air to reach the soil, and provides limited control of the weeds which emerge from the earth. However, the weeds which start in the mulch tend to send their roots down through the fabric into the ground, where they thrive in the moist environment which the fabric preserves. The roots of the weeds become so enentangled in the fabric that they typically cannot be removed without pulling up or tearing the fabric.
What is needed, therefore, is landscaping film which allows an adequate amount of water and air to reach the soil, but is effective in reducing weed root penetration.